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    SubjectRe: gcc 4.5.1 / as 2.20.51.0.11 miscompiling drivers/char/i8k.c ?
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    On Mon, Nov 15, 2010 at 7:45 PM, Jeff Law <law@redhat.com> wrote:
    > On 11/08/10 03:49, Richard Guenther wrote:
    >>
    >> On Mon, Nov 8, 2010 at 12:03 AM, Andi Kleen<andi@firstfloor.org>  wrote:
    >>>
    >>> Andreas Schwab<schwab@linux-m68k.org>  writes:
    >>>>
    >>>> The asm fails to mention that it modifies *regs.
    >>>
    >>> It has a memory clobber, that should be enough, no?
    >>
    >> No.  A memory clobber does not cover automatic storage.
    >
    > A memory clobber should clobber anything in memory, including autos in
    > memory; if it doesn't, then that seems like a major problem.  I'd like to
    > see the rationale behind not clobbering autos in memory.

    Non-address taken automatic storage. (note that we don't excercise this
    in optimization yet)

    It's difficult to model thins kind of non-aliased memory with this kind
    of aliasing mechanism (apart from taking all asms as clobbering
    everything as we currently do).

    Richard.

    > Jeff
    >
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